C

CACK AND EDE Dialect. Left handed or just awkward and accident prone. See Keggy handed.CADGE or CEDGE Dialect. Beg, borrow, but not steal, that would be wrong.

CAKE The surface of the burning coal in the firemouth of a bottle oven.

CAKE One of several slabs of clay found in a filter press after the pressing cycle finishes. The filter press removes water from slip to produce plastic clay ready for wedging before balling up.

An early filter press in the sliphouse.
Sliphouse men removing the plastic clay cake from the press after the pressing cycle.

CALCINING and CALCINATION Process. Heat treatment at high temperature (red heat) in specially constructed kilns to create physical and chemical changes in pottery raw materials. Eg: Flint or Bone. Calcination drives off organic matter and combined water. After calcination bone ash can be ground to a fine powder and added to the bone china pottery body.

Calcining Kilns at Twyfords, Cliffe Vale, Stoke on Trent, England.

CALCINING KILN A calcining kiln is not used to fire pottery but to prepare some of the raw materials used in pottery bodies. Before flint or animal bones can be added to the body recipe they have to be crushed to a fine powder. When they are in their raw state they are impossible to crush as they are too hard but if they are burnt or calcined they become brittle and can be powdered with ease. (There was no particular reason why such ovens should be bottle shaped other than to get a good upward draught.)CALGON Material used during the process. Actually sodium phosphate. Used as a deflocculant for clay slip and glaze suspensions.

CANEWARE Material. Pottery body. Pottery of a dark cream body, produced from a buff-burning clay. The designation is derived from the cane-like colour of the ﬁnished ware. Both dense and lighter cane-wares are produced in pottery, to accommodate various requirements. Some canewares supplied in table articles are much esteemed.

CANST, CONST, COST, CON-YER Dialect. Can you?

CANT Bottom outside edge of a saggar. Should be rounded to help the saggar resist thermal and mechanical shock during firing and rough handling.

CANT Specially shaped metal tool used by the saggar maker. Piece of used to smooth around the outside bottom edge of a saggar to create a bevelled edge, making the saggar easier to lift.

CANT Dialect. To tell tales or to 'spill the beans' on someone.

CANTEEN Once seen as an essential area of a potbank for the health and well-being of potters. Busy for only two short periods during the day - at breakfast and at lunch (dinner).Some canteens were elaborate affairs.

At Wedgwood in the late 1960s and early 1970s the canteen was huge with seating available for up to 300. Workers (ie those who created the pots) used one area of the canteen while staff (those who administrated) used another screened off and more elaborately decorated area. Them and us. Us and them. Pity - but true. The canteen was multi-functional since it was used for arts and crafts displays, as a gym and for amateur shows. It was also used for major announcements to workers and staff.

At Twyfords in the early 1980s the canteen at the Etruria Works was divided into three - workers, staff and directors. The staff canteen was sometimes used for visitors on training courses. The main workers' canteen, when it was built, had an elaborate stage with a proscenium arch designed in the Arts and Crafts Style by the important designer Gordon Forsyth (1879-1952) and painted by pupils from Burslem School of Art.

Proscenium arch for Twyfords Canteen designed by Gordon Forsyth 1879-1952

Activity in the Canteen at Twyfords - probably 1920s - facing the proscenium arch.
Notice the portrait of Thomas William Twyford, top right

CANTON BLUE Material. Colour. A mixed shade of blue, derived from a cobalt base, but lighter and greyer than the ordinary underglaze blue, or cobalt blue. Canton blue is sometimes described as “mulberry.”

CAPE ONTH BRICKS Dialect. "You take care, now"

CARRERA Material. Type of pottery with a particular recipe and requiring particular firing conditions. Peculiar to Josiah Wedgwood. Statuary porcelain. Also known as Parian Ware from Spode.

CARTON PACKER Occupation. Male or female. Warehouse or packing house. The person packs pottery product into ready made corrugated boxes of a particular shape, specially created to accommodate the products. Dinner ware and tea ware was/is packed in these boxes. Also packs of all plates, or all cups.

CASE or CASE MOULD A POSITIVE mould. Giving the same shape as the original model but created in several parts in several parts. Made (taken) from the block which is the master mould and therefore the NEGATIVE of the model. Click here> mouldmaking

Positive MODEL

Negative BLOCK - The Master Mould, formed from the model

Positive CASE - similar to the original model but formed from the BLOCK

Negative WORKING MOULD formed from the case

The positive CAST PIECE

CASTLE A town near to Stoke. Newcastle-under-Lyme

CASTER Occupation. Clay end. Male or female. A potter who creates clay pots using the casting process. See below.

CASTING Process. Potting department. More strictly known as 'slip casting.' The process by which some types or styles of pottery products are created. Casting slip is poured into a Plaster of Parismould until full. The porous plaster immediately begins to absorb water from the slip and a skin of plastic clay builds up on the surface of the mould. The skin gets thicker as the slip is left in the mould. The absorption of water by the mould causes the level of casting slip at the head of the mould to drop. The mould is sometimes topped up occasionally during the casting process. Once the cast has reached the desired thickness, the liquid casting slip in the mould is poured out, leaving only the build up of clay particles against the mould face. After a time, as the clay dries, it draws away from the mould face and becomes firm enough to support itself and can be released from the mould. The mould is opened or in the case of a one piece mould tipped gently upside down to release the cast. The cast piece is then set aside and when leather hard or cheese hard is ready to be fettled and sponged.

Casting 1960

CASTING SLIP Very fluid slip of high solids content (high pint weight) made up of clay body, deflocculant and water.The consistency of runny custard. It is used in the casting process to form pottery shapes.

CASTING SLIP SCRAPS Left-overs and cut-offs from the casting process. The scraps were returned to the casting slip blunger [in the sliphouse] and recycled. Casting slip was a different consistency to slip in general, for it contained sodium silicate. (This potbank definition was supplied courtesy of Alan Hopwood, 6 March 2016. Thanks Alan!)

CASTING SPOT Pottery body fault, sometimes found on cast pottery. Discoloured spot. Occurs where the stream of casting slip first hits the plaster of Paris mould during the casting process. Results from the localised orientation of the plate-like particles of clay in the liquid pottery body. Sometimes called flashing.

CASTLE The place. Newcastle-under-Lyme. Not in The Potteries. Oh no. Too posh for that!

CATTLE BONES Pottery body raw material. When calcined, the bones can be crushed and ground to a fine powder and added to the bone china body. The bone china recipe can include as much as 50% of cattle bones. The best bones used in bone china are the shin bone of oxen. Horse bones are useless since they too spongy.

C.C. WARE Type of pottery. A term applied to the cheaper cream-coloured earthenwares - those which have not been whitened by means of a blue body stain in the recipe. Pudding bowls, bakers, and similar articles produced as quick-selling, everyday lines, are normally supplied in C.C. ware.

CELADON Type of grey/green coloured glaze. Applied relatively thickly to stoneware or porcelain. Sometimes matt, sometimes glossy when fired. The glaze was first used in China and is especially associated with the Sung Dynasty. The colour is created by a small amount of iron oxide. It is translucent and is often combined with a carved decoration which shows through the glaze.CELLULOSE WARE Pottery which is not glazed and fired for a second time. A cellulose lacquer is sprayed onto the surface of the once-fired biscuit ware to create a hard, glossy decoration. Basically cellulose-based paint. Dates from the 1930s.

CENTRING Process. Skilled process for men or women. The means by which a circular shaped pot (a plate, for instance) is tapped and nudged so that it lies perfectly centred on a small revolving round table. Centring is also the process which a thrower makes sure that the ball of clay which he will use to throw a pot is perfectly in the middle of his throwing wheel.

CERAMANT Brand name of a particular type of pottery made by Twyfords of Stoke-on-Trent, sanitaryware manufacturers. High temperature, twice fired fired. White vitreous (non porous) clay body of very fine texture with a glazed white or coloured surface. The clay is vitrified in the firing process so that to all intents and purposes it is non porous and will not absorb moisture.

CERAMIC

Hard, brittle, heat-resistant and corrosion-resistant non-metallic inorganic material made by shaping and then firing a clay (or other non-metallic mixture) at a high temperature. From Greek keramikos, of pottery, from keramos, potter's clay. Pottery, porcelain, earthenware, china, bone china, tiles, sanitaryware, bricks, floor quarries, sewer pipes, glass, technical ceramics. All ceramics lend themselves to manufacturer in a certain way, the essential part of which is the application heat to render them hard and resistant to their environment.

CERAMIC

An environmentally friendly and sustainable product, largely consisting of the natural and widespread raw materials kaolin, clay, feldspar and quartz sand. It can therefore be produced economically in large quantities, can be safely used in contact with foodstuffs or in the bathroom and is completely recyclable at the end of a long product life.

CERAMIST or CERAMICIST

Profession. Either the technician who makes it all happen, or a craft potter. Brilliant occupation - possibly the best job in the world, so they say.

CERAMIC CHANGE

The metamorphosis of clay during firing. The irreversible change from clay to pot upon which the whole of the craft and industry is founded. The change which takes place during the firing process at around 600°C when clay loses its chemically bound water molecules and can no longer be broken down by water. Once this change has occurred it cannot be reversed. Ever. The ceramic change converts fragile and crumbly dry clay from Mother Earth into hard brittle pottery. This is both a chemical and physical change to the structure of the clay. CERAMIC COLOURS Mainly carbonates and oxides of certain metals which are added to a glaze or a clay to create coloured effects. The commonly used are cobalt carbonate, cobalt oxide, chrome oxide, red iron oxide, and copper carbonate. These colourants can create a multitude of different colours depending on other materials they interact with and to which temperature and in which atmosphere (oxidising - oxygen rich, or reducing - oxygen starved) they are fired.

CHAMOTTE Material used in the process. A component of grog. A ceramic material formed by the high temperature firing of a refractory clay, after which it is crushed and graded to size. Used as the a non-plastic component of some clay bodies. (Thanks to Mick Moran for bringing this one to my attention January 2011).

CHARACTER JUG Similar to a toby jug but usually just head and shoulders and definitely no knees on show! Why? Because only Toby Jugs show knees!

CHARGE The measured amount of material put into a mill or blunger for further processing.

CHARGER Large shallow bowl or platter. Difficult to make on a potbank.

CHARLOTTE READ Extraordinary designer and potter. Born in 1885 into the well known Rhead family. Her father was the designer, Frederick Rhead. Her first employment was at T & R Boote in Burslem where she learned the art of tube-lined decoration. Tube-lining is the piping of a fine trail or line of soft clay onto the body of a pot, giving an outline for further decoration.

Charlotte, or Lottie as she was sometimes known, spent the rest of her life designing and decorating for various companies in the same area. She stayed at T & R Wood until 1913 when she joined her father who had recently been appointed Art Director at Wood & Sons. In 1920 her father and Harry Wood set up Bursley Ltd, to produce art pottery and Charlotte joined the new company. She moved to Burgess & Leigh, producers of Burleigh Ware in 1926. In 1931 she joined A G Richardson, working first at the Gordon Pottery and then at the newly re-built Britannia Pottery. She rejoined Harry Wood in 1943 and stayed working at H J Wood Ltd in Burslem until her death in 1947. Her work, which is highly prized by collectors, is usually in muted colours - pinks, blues, greens and browns - and of very high quality.

CHAISE See CHAYS (CHAYZ) below.

CHASED Engraved or incised. A decoration.
CHASED Gold Decoration. Gold design created on the newly-fired gold surface which is still matt and unburnished. The pattern is created on the surface using a finely pointed agate stone. The stone is drawn over the matt surface to create a polished effect. Expensive to produce and very skilled.

CHATTERING Fault. Decorating fault. Found on banded or lined ware. The bands or lines look incomplete and inconsistent.

CHAYS or CHAYZ Dialect. Nourishment to eat with your crackers and wine. Or on oatcakes grilled so that the chays (chaise) becomes soft and runny and dribbles down your chin. Messy but scrumptious. Local delicacy.

CHECKER Occupation. Usually in the warehouses. Also known as spot checkers whose role in the potbank is to inspect and constantly check that the work and the product is up to the standard laid down by the management.

CHECKERS Part of a Bottle Oven>. Refractory brick (the size of a standard building brick) placed in above the firebars in the ashpit of a bottle oven's firemouth to retain the coal.

CHEEKS Part of a bottle oven. The inside sides of the firemouth in a bottle oven.
CHEESE A saggar. Equipment. A particular shape of saggar - one of many different shapes.

CHEESE HARD Name for the condition of the clay piece prior to thorough drying and firing. Sometimes known as leather hard. Not soft and flabby. Not hard crisp and brittle. Reasonably easy to handle. Also known as Chays-ard.

CHEESE WIRE Equipment. Used during wedging to slice a lump of clay into two pieces. Also used by the thrower (or his baller) to remove his thrown pot from the wheel.

CHERT Material used during the process. In a pan mill. Siliceous rock. Modular and tabular. Chert stones are used as pavers or runners in the old style paddle type pan mill for grinding potter's materials. May also be used to line ball mills.

CHIMDY Dialect. Chimney.

CHINA Type of pottery with a particular recipe and requiring particular firing conditions. Sometimes this word is used very loosely to mean all pottery - but that would be wrong.

CHINA BEDDER Occupation. Ovens department. Usually male. He buries bone china clay pieces (plates and saucers) in preformed alumina dust so that during firing the clay keeps its shape and doesn't warp.

CHINA CLAY Kaolin. A major component of pottery body recipe formed by the decomposition of granite. White in its raw state and white after firing. A primary clay washed by high pressure water hoses from the sides of deep open mines. Major deposits in Cornwall, England. China clay was first discovered in England in the 1740s near St.Austell, on western flanks of Dartmoor and on the western and southern parts of Bodmin Moor. The high pressure water is are directed at the sides of open deep clay pits. The fine clay forms a slurry and is washed down into settling tanks, prior to drying and transport. China Clay is also a component of paint, paper, pharmaceuticals, rubber, plastics, and sealants.

CHINOISERIE Decoration. European imitation or adaptation of Chinese art and motifs

CHINTZ or CHINTZWARE Pottery decoration. Onglaze. The piece is covered with a dense, all-over pattern of flowers similar to chintz textile patterns. A form of transferware where the pattern is applied by transfer printing or litho transfer. Not painted by hand. The main firms making chintz ware were Grimwades (Royal Winton), A.G. Richardson & Co. (Crown Ducal), James Kent Ltd, and Shelley Potteries, amongst others. (Many thanks go to Jayne Packer for sending me this word, Oct 2015)

Chintz

CHIP Pottery fault. Small piece knocked from the edge of a pot rendering it faulty and unsightly. Some sellers on eBay describe a chip as a 'nibble' - perhaps to make it sound less bad.

CHIP Nourishment. With fried fish on a Friday! Or during the rest of the week served with gravy. Strange but true!CHIPPED Pottery body fault. Chunk missing.

A chip on the foot rim of a pot by Norman Wilson, of Wedgwood

CHITTERING Pottery body fault. Looks like a series of small ruptures to the edge of the clay ware. Caused by bad fettling or towing.

CHITTERED and CHITTERED EDGE Pottery fault. Cracking found on the edges of flatware caused by poor and careless fettling of plate edges when using a metal fettling tool.

CHOCK Possibly a chum or a chuck.CHONG Dialect. (With thanks to @pottrays for the idea)

CHONNOCK Dialect. Turnip. Necessary ingredient in lobby. Sometimes CHANNOCK but not often. TRUE STORY - My old boss, Fred Read, at Wedgwoods, Barlaston, in 1968, told me about his time as a lad when he went to the pictures on Saturday morning to see the 'penny rush' films. Times were bad and people were so very poor. They didn't have the money for the luxury of sweets or ice creams but they did have vegetables. One day he was sitting there enjoying a film 'and was hit on the back erv me yed with a chonnock!'

CHOPS Dialect. "Hers got some chops on her." Talks too much. On and on about nothing in particular. Without going anywhere in the conversation and without developing a story but talking endlessly without a meaning to what is being said. On and on it goes without letting else in on the conversation, creating a true boredom amongst those listening but without knowing that this would be the outcome. Getting carried away, 'chopsing' along endlessly repeating the story or particular words without listening to anyone else present. Been there done that, got the tea shirt. Knowing everything about everything and everyone else is wrong in the opinion of thee one who is chopsing. Have you heard the one about is a typical way of starting but not necessarily. Do you get the drift?

CHUCK Equipment. Potting department. Former used to hold a pot in position on the turner's lathe or wheel while the foot is being trimmed. Also a chum.

CHUM Equipment. Tool. Shaped block of wood or plaster with a domed top. A bat of clay can be roughly shaped over the dome before being placed in a mould for jolleying large pieces of holloware. Moist flannel is usually placed over the dome.

CHUM Best friend. Person or animal. Which is nice :) Might also be marra.

CHUNTERRIN Dialect. Moaning about someone or something to another? As in "ayes chunterrin on abite eet agen". (Word courtesy of Stephen Knapper, 9 March 2014)

CHURCH BATTER Description of the shape of a bottle oven. Actually very curvy and bottle shaped. (Mountford, kiln builder).

Twyfords Cliffe Vale - Church batter
Photo: Virtue, London Date: 1900

CIRCS A particular shape of brick used in the construction of the bottle oven chimney. Circs are curved bricks and they form the circular top of the oven chimney. (Mountford - kiln builder).

CISTERN Sanitaryware. Ceramic (or stainless steel or plastic) tank containing water used for flushing the WC. Also the large cold water tank found in older houses which have a low pressure, gravity fed, plumbing system. Nothing to do with the Cistern Chapel in Rome.

CLACK As exclaimed by the choking potter "Eets got stuck in me clack." The Epiglottis. This is a flap that is made of elastic cartilage tissue covered with a mucous membrane, attached to the entrance of the larynx. It projects obliquely upwards behind the tongue and the hyoid bone, pointing dorsally.

CLAM UP Shut up. Also to seal the bricked-up clammins with soft clay to prevent air entering during the firing process.

CLAMMINS Part of a bottle oven. Sometimes called clammings. The brickwork created to seal the entrance to a bottle oven before and during firing. Sometimes known 'clammins arch.' Bricked up and sealed before firing and knocked down again after the fire to gain entrance to the fired ware. The clammins are built two bricks thick with the lowest trial hole at about the same height of the bags. The clammins fill the wicket>

Clammins - bricked-up entrance to the oven.
Seen here being bricked up prior to firing 1978

CLASSIFIER Occupation. Usually in the warehouse. Sorting out faulty products into types, such as pinholed, crooked, firecracked, so that management can see where the biggest problems, during processing, are coming from. A step-up from a sorter. A step down from a supervisor. Career structured in the warehouse!

CLASSIFYING Process. What a classifier does. Sorting out faulty products into types.

CLAY

Material. A component of pottery body recipe. Mother Earth, extracted from the ground. The mud from under your feet.A mineral which can be moulded. The term covers a huge range of natural substances differing greatly in appearance, texture, and chemical and physical properties. Some clays (such as kaolin) contain 90% clay-substance others (such as brick clays) contain as little as 30% clay substance. But all clays have a characteristic in common - they are all plastic when wet and when dry become rigid. At a microscopic level, the particles of clay have a flat plate-like structure giving them this plastic-like property. They can be made plastic once more by the application of more water and thoroughly re-wetted. But when fired at high temperature all clays become permanently and irreversibly non-plastic and mechanically stronger. The 2 most common clays are Ball Clay and China Clay (Kaolin). Clay is one of the raw material components of a ceramic 'body.' Article Source: http://EzineArticles.com/7054895CLAY This remarkable description of clay by the late Daniel Rhodes (1911 – 1989) is a short extract from 'Clay and Glazes for the Potter' first published 1957. Clay is a deceptively simple material. It is cheap and abundant. Often it may be found in the earth already softened with moisture and ready to be worked. It keeps forever and improves with age. Unfired clay objects may be crumbled, mixed again with water, and made into something else. As a material it is soft, pliant, plastic, impressionable, without grain or direction. It can be modelled, pounded, flattened, rolled, pinched, coiled, pressed, thrown on the wheel, cast into moulds, scored, shredded, pierced, stamped, extruded, cut, or spun.

Small and delicate objects may be made with it, or massive architectural forms. Clay shapes may resemble the looseness of a crumpled dishrag or may have the precision of electronic machines. In colour, objects made from clay may be dazzling white, creamy, red, orange, yellow, grey, brown, black, or textured with spots, streaks, speckles, flashings, and tintings. They may be smooth and ivory-like, or rough, sandy, gritty, or harsh. Fired clay can have a translucence approaching that of glass or a density like that of the hardest stone.

All these possibilities are to be found in the craft of ceramics. Clay, formless in the earth, is laden with potential. It responds to shaping, to drying, to firing, to blending and combining, to texturing, to smoothing. A given lump of clay may become a roof tile, a brick, a votive sculpture or effigy, a water jug, a child's toy, or a venerated tea bowl or vase in a museum case admired by thousands. The knowledge of ways to make things from clay and to fire them brought about a significant advance in man's standard of living. Bricks, tiles, sanitaryware, drain and water pipes, dishes, bowls, cooking pots, and sarcophagi have helped to make life easier and more pleasant, and have lent dignity to burial.

CLAY BANK An area on a potbank (earthenware or fireclay works) where clays are stored outside to allow them to weather before use. Weathering allows soluble salts to be leached out in the rain.

CLAY BUMPER Equipment used during building a bottle oven. A specially shaped trowel used to apply ganister (very stiff fireclay) to the crown of a bottle oven during building.

CLAY DIPPER Occupation. Potting department. Some pottery is 'clay dipped.' That is, the clay pot is allowed to dry and is inspected in the green house. Then it is then dipped in glaze and glost fired without going through the biscuit fire.

CLAY END Potting department. Where it all starts on a potbank!

CLAYHANGER

Novel by Arnold Bennett set in The Potteries. Written between 1910 and 1918.

CLAY STIFFNESS (Sometime called hardness) Clay bodies must be of the correct stiffness in order to optimise the forming process. The body of the clay should be of standard stiffness and plasticity to maintain consistency during forming, either by machine (jolley or jogger) or by hand (throwing or slab building). Some bodies soften over time, others stiffen but re-soften as soon as they are wedged. Each body has its own specific water content percentage which corresponds to specific stiffness. Usually, the more plastic it is the more water is needed. See 'pig stick' here>CLAYING UP Process. Clay end. During blocking and casing. During the creation of the original block (or master) mould the mouldmaker has to be certain that he creates no undercuts which will stop the mould from delivering the clay piece after it is cast. In order to do this he builds clay dams onto the model using small lumps of clay to build them. This is claying up.

CLEAN ARK Equipment. Huge storage tank for clay slip which has been lawned (sieved) and magnetted to remove impurities.

CLEARING Process. Emptying a fired bottle oven. Taking out the fired pieces and passing them on to the next process - usually in the warehouse.

CLEARING HOLES Part of a bottle oven. Also called shoulder holes on some potbanks. Holes in the crown of the oven, positioned above the bags, and permanently open and to allow the escape of burnt gases and smoke from the firing chamber.

CLINKER Lumps of fused ash formed from coal burning during a bottle oven firing and found in the ash pit and mouths of the oven. Clinker can form over the firebars during the fire and particularly if small pieces of coal or slack are used. This clinker will prevent a sufficient draught for the fire. This clinker needs to be punched out but this allows cold air into the kiln and this, in turn, retards the firing. Lets face it - clinker is bad news for a potter.

CLOBBER Clothing or gear. "You have too much clobber in the wardrobe!" (Nice suggested entry from Samantha Calvert, June 2014)

CLOBBER Hitting someone hard "He clobbered him one". Similar to lamp! (Suggested entry from Samantha Calvert, June 2014)CLOBBERED A form of overglaze pottery decoration. See clobbering below.

CLOBBERING 1) Process. Decorating dept. The practice of adding extra surface decoration to pottery manufactured by someone else, with or without their permission.

CLOBBERING 2) Process. Decorating dept. The filling in of 'white space' in a transfer printed design by adding colour and/or pattern by handpainting. On glaze.

CLOGS Clumpy footwear with a wooden sole and leather tops and laces. The wooden sole was protected with nailed-on metal bands. Uncomfortable but healthy.

CLOT May be, an idiot.COADE Coade Stone. Terracotta made in Lambeth by Eleanor Coade from 1769. Closely imitating stone in its colour and texture.

COAL Material used in the Pottery making process. Fuel. Stuff of The Potteries. Florence Nuts. Used in the Last Bottle Oven Firing more> Combustible black rock carbonized plant matter found mainly in underground seams. Interestingly 'young people' are unaware of its significance - or even how to light it! The Last Bottle Oven Firing used coal: more here>

Coal

COALOLE Cellar in a terraced house where coal is stored. The cellar has a doored opening to the pavement in the street above to allow delivery of the coal.

COBALT BLUE Cobalt Blue is one of the oldest manufactured colours known. It is a very deep blue and was found on pottery buried with the Egyptian Pharaos. It remains a popular colour and is used to colour plastics, cement, glass and numerous other substrates. The ingredients of this blue are cobalt oxide and silica. The Egyptians probably did not understand the chemical process involved but found that by heating naturally occurring cobaltite (raw cobalt ore) and sand or quartz, they obtained a deep blue powder. The heat had turned the cobaltite into small amounts of cobalt oxide which would react with the silica in the quartz to produce Cobalt Blue.Cobalt Blue was first seen in Britain in the 1570's on Delftware imported to London. However it was not made in the Potteries before 1700. The manufacture of Cobalt Blue in the Potteries in the eighteenth century began with the mixing of pre-prepared cobalt oxide imported from Germany, and silica. These powders would be mixed with shovels on the ground which was a very dusty process.For many years earth kilns had been used for the firing of pottery, and colours were also fired in this way. The usual method of firing was to dig a shallow pit into which charcoal, wood or coal were placed; the pottery or colour-ingredients would be placed over the fuel and the whole kiln, when lit, would be insulated with either stones or a layer of clay. Modern kilns are far more technical and easier to control.Fired colour is usually very lumpy as a result of the chemical reactions that have taken place, and so to obtain a manageable substance for easy application to ware. These lumps are ground down to a powder using an adaptation of the corn-mill, where colour would be crushed between revolving Chert stones and a stone lined metal base, (it would be originally driven from a water wheel). Modern processes are much more elaborate than these early methods of making colour. A great deal of testing is now necessary throughout manufacture. However mixing, firing and grinding remain the main elements of colour manufacture even though they are now largely mechanical operations.

COBALTITE Material. A sulfide mineral composed of cobalt, arsenic and sulfur, CoAsS. It contains up to 10 percent iron and variable amounts of nickel. Structurally it resembles pyrite (FeS2) with one of the sulfur atoms replaced by an arsenic atom.

COBBED UP Dialect. Miserable. Very miserable. Hates life. Hates everything. Got out of the wrong side of the bed? Why bother?

COCK STRIDE Dialect. Not far. Near. (not rude)

COCKWOOD Scrap timber. (Many thanks go to David Braodhurst for sending this word March 2016)

COCKLE Actually COTTLE but mispronounced. Equipment. Mouldmaking department. Essential in mouldmaking. A wall or dam made from some sort of stiff material used to create the sides of a case mould before liquid plaster is pured into it. The cottle can be made of exotic material such as old lino pieces, marley flooring or roofing felt!

COD or COD PLACER Occupation. The foreman responsible for placing the bottle oven. Experienced and knowledgeable man who knows how and where the products should be placed in the oven to get the best fire.

CODGE Dialect. Codge-up. As in bodge or cobble it for a temporary repair.

COFFIN Equipment. Large rectangular open top box for transporting product around the factory. Approx 5 feet by 2 feet. With legs. Moved on a jack truck.

COGGLE Equipment. Clay end. Small wheel with raised pattern around the rim, which when rolled along a plastic clay surface leaves a band of relief pattern. Usually formed with damp unfired clay.

COIL POTTING Process. Technique for making pots by building up the sides using a series of coils of clay. The coils are first produced by rolling out cylinders of clay which are then wound round and smoothed down to create the shape. Used widely by potters in many parts of the world either to make the whole or part of a pot.

Coil potting

back to top>COLD CONE An area of 'cold' found in tunnel kilns. (Transactions of the Brit Ceram Soc. Vol 75)

COLLAR Plaster ring on top of a holloware mould.

COLLARING Pottery fault

COLLAR STUD Loosened on warm days. Frowned upon, otherwise.

COLLOID A substance microscopically dispersed evenly throughout another substance.

COLOUR - CERAMIC COLOURS Mainly carbonates and oxides of certain metals which are added to a glaze or a clay to create coloured effects. The commonly used are cobalt carbonate, cobalt oxide, chrome oxide, red iron oxide, and copper carbonate. These colourants can create a multitude of different colours depending on other materials they interact with and to which temperature and in which atmosphere (oxidising - oxygen rich, or reducing - oxygen starved) they are fired.

COLOUR MAKER Specialist manufacturer of ceramic colours for use in the pottery industry

COLOUR PRINTING- UNDERGLAZE

Josiah Spode I is credited with having perfected the technique of underglaze printing on blue on earthenware in about 1784. Additional underglaze colours were not to be successfully produced until nearly forty years later. The B series of Spode patterns, a numbering system used for underglaze designs, was introduced in about 1822. Prior to this, colour printing other than blue was restricted. Colour was achieved by overglaze enamel decoration or hand coloured blue, brown or black prints. Black, purple and ochre were available but were not popular colours for ceramic decoration. It was only after much experimentation that new, mainly chrome based, colours were introduced that could withstand the high temperature glost firing required for underglaze decoration.
The new colours 'bonded' less well with the glaze than the blue; this meant that the appearance was less translucent and luscious but at the same time it led to a sharper image. Chrome Green which contains no cobalt gives a particularly sharp image as can be seen in the clarity of detail on items decorated with the Byron Views pattern. It was the most successful colour after blue. Chrome Green produced by the use of iron chromate, was introduced in c1822 followed by a series of other colours including brown, puce, orange and a blue-grey known as Paynes Grey. A common colour, particularly for sheet patterns is a khaki green known as 'Pigmuck Green' (for obvious reasons!), it is thought to have been made from the dregs of other unused printing colours. Underglaze pink was introduced around 1833 by adding a small amount of tin oxide to iron chromate; early examples are rare but the colour has been reintroduced several times in the history of the company.
Spode was responsible for the first two-colour printing technique. The process, which was introduced around 1824 involved the use of a resist substance known as 'ackey' (the Potteries term for sticky and dirty). This protected a hardened-on print before applying an all-over sheet pattern. This allowed an image to be placed within a printed background of another colour. Spode's Tumbledown Dick on Marble Sheet is a classic example of this technique.
Many more dinner plates were made than any other shape but printed patterns can be seen on all shapes of table ware as well as toilet ware including leg baths, foot baths, chamber pots and bidets. Dessert wares were more often handpainted and gilded as they were subjected to less wear. Underglaze decoration for dinnerwares was popular because the design was protected under the glaze from the sharp steel cutlery of the time.

COMBED or COMBING Type of decorative process where a toothed instrument is dragged over a soft clay surface, sometimes through a layer of slip to create the decoration.

COME UP Process. During the firing of a bottle oven, near the end when the temperature of the oven is reaching its peak, the fireman (or sitter up) will be careful to ensure that the temperature has "come up" correctly without dropping back at all.

COMMONITES Common size of saggar. Common height of about 8 inches. Alfred Clough, February 1978. It was possible to stack 3 dozen (36) cups in a 'commonite.'

COMPRESSION STRENGTH (sometimes known as compressive strength and not to be confused with 'tensile' strength)The ability of a pot to withstand a crushing load.

CONE - actually SEGER CONE Equipment. Pyrometric cone. Device for measuring the heat-work imparted to pottery pieces during the bottle oven firing. Pyramid-shaped. These devices are formulated from different mineral mixtures and numbered accordingly. They are placed in a kiln so they can be viewed during firing and when a cone begins to bend it is closely monitored and the firing is terminated when it reaches a specific position.

CONNA or CONNER Dialect. Cannot. As in shonner, conner, wutner.

CONING UP Process. Potting department. During throwing. The action performed by a potter on a potter's wheel. The potter applies pressure to the clay in such a way that the clay forms into a cone shape. Coning is done so that the clay can be centered more easily and air bubbles will be forced out of the clay.

CONTINUOUS OVEN Equipment. Shaped like a tunnel with firing zone in the centre. Truck of ware are continuously pushed in a train through the tunnel on rails. In the firing zone the ware is fired. Biscuit, glost, hardening on or enamel firing. May be straight (about 100 yards long) or circular/

COPPER PLATE Equipment. See Copper. Created by engravers using gravers for use during the transferring process.

CORAL RED Material used during the process. Red enamel for hand painting.

CORE Central removable part of a plaster mould used for solid casting.

CORK Foundations of a bottle oven. All bottle ovens had to have a very firm foundation. 3 to 4 feet of earth should have been excavated from the plot of a new oven and the hole filled solidly with broken bricks. Smaller spaces between the bricks should have been filled in with shards and then fired sand used to smooth it all over as a basis for the brickwork of the oven. The cork was raised or domed as the start for the oven flues. CORNISH STONE Component of pottery body recipe. Same as china stone. In the UK it is found in the St.Stephen's and St.Denis districts of the St.Austell granite mass, Cornwall. Granite partly decomposed by the action of fluorine and other gases. It acts as a flux . Contains feldspar.

COSS Dialect. Curse. Angry shout.

COST - CONST - CANST - CONYER Dialect. Can you?

COST KICK A BOW

"Cost keck a bow aggen a woe, y'ed it till thee bost it?"

A Potteries Classic! This is a very special sentence in Potteries Dialect.

It isn't used in everyday speech. But a stranger to the six towns would immediately be confronted with the words and asked to explain what it all meant. Potters enjoy that!

(Many thanks go to Jane Pancutt for reminding me to include this important sentence. Oct 2015)

COTTERS Pieces of broken saggar used as wedges to prevent any movement of the top bricks in a bricked-up clammins arch.

COTTLE Equipment. Mouldmaking department. Essential in mouldmaking. A wall or dam made from some sort of stiff material used to create the sides of a case mould before liquid plaster is pured into it. The cottle can be made of exotic material such as old lino pieces, marley flooring or roofing felt!

COUPE SHAPE A particular shape. On plates, a coupe shape has no shoulders or distinct rim. From the French 'cut'.

COVER Kiln furniture. Flat cover fits on the top of a crank. Protects ware from falling dirt and holds the pillars of the crank in position.

COVER COAT Material used during the process of manufacturing lithos. A flexible and very thin plastic coating which keeps the printed design together. Often brightly coloured to assist the lithographer when placing the decoration in position on the piece.

Cover coat before firing.
Stained yellow so that it can be seen clearly

CRACK CRACKED and SOUND CRACKED Faulty pottery.Pottery which was found to be cracked after its glost firing was usually scrapped as useless. It was described as LUMP or PITCHER and usually sent to the shraff tip. However, some entrepreneurs in the industry were able to make money from selling cracked pottery - depending on how cracked it really was! Here, to explain is a quote from Brian Milner. He was one of those entrepreneurs in the 1960s, 70s and 80s. "We used to buy China teacups from Ridgways. These were termed "crack cracked" and "sound cracked". I am not kidding. They were [packed] 40 dozen in a teachest and we used to buy about 12 chests every 2 weeks. We would sound every one of the "crack cracked" and find a lot of sound ones which we used to decorate and we were still able to sell the really cracked to market men."CRACKED Firemouth doors or dampers in a bottle oven which are slightly open. Also known as jacked.CRACKLE GLAZE Type of glaze. Decorative effect. Produced by firing a glaze of high expansion on a low expansion pottery body. A crackle results. Also found during raku firing. Stains are often rubbed into the crack lines to heighten the effect.

CRANK Equipment.Kiln furniture. Refractory support for flatware and tiles in glost and enamel firing. The flatware rests on replaceable pins which rest in sockets in the crank posts. The pins are so designed as to make minimal marks in the glazed surface.

CRATE Large wooden box-shaped container used for packing finished pottery goods prior to dispatch. Filled with pottery and packed tight with woodwool or straw. Crates were made for the safe transport of bulk pottery items, and were just one of the ancillary trades which supported the pottery industry. Images here>

Lorries loaded with crates packed with pottery sanitaryware

Case and Crate packed with pottery ware using straw as the packing medium

CRATE MAKERS Occupation. Most usually men. Those who hand built crates for use in pottery packing. See above.

Two cratemakers at Brocksford Street, off King Street, Fenton, Stoke-on-Trent
Photo: Charles Trelfa From collections of the Potteries Museum Art Gallery. Date: 1949

CRATE MEN Occupation. Not cratemakers. Theses men packed ware into crates as it came from the oven.

CRAWL or CRAWLING Glaze fault.The fired glaze appears patchy. Shrinkage or crawling back of the glaze leaving exposed body after glost firing. Caused by a poor bond between the body and the glaze, usually because of dirt or grease on the biscuit body before dipping. Affected areas can vary in size from a small pinhole to several square cms. It is the result of different angles of contact between the sprayed glaze and the clay body. Crawling is quite prevalent in once fired ware.CRAZING or CRAZE Glaze fault. A network of fine surface cracks in glaze. Occurs due to stresses created in the glaze by expansion of the body. Results from a mismatch of thermal expansions of the glaze and body. The craze pattern can develop upon removal from the kiln or even years later. Crazing happens when a glaze is under tension. The most stable glazes are under slight compression. While crazing is classified as a glaze defect, it can also be corrected by adjusting the clay body. The goal is to adjust the glaze and clay body to cool at a compatible rate with the glaze coming under slight compression. Sometimes used to decorative effect - particularly in "art" or "craft" ceramics.

Crazing as a fault, on the left. Crazing as decoration on the right

CRAZING POT Equipment. An autoclave using steam, under pressure, to enhance the formation of crazing under laboratory conditions for testing purposes. Steger's Crazing Test is a method for the assessment of the glaze fit. It is undertaken by measuring any deformation on cooling of a thin bar that was glazed only on one side. A common method of testing glazed ceramic ware for crazing resistance is to expose pieces of ware to the steam in the crazing pot at a minimum of 50 psi.

CREAMWARE Earthenware body of a fine texture. Naturally cream coloured. Developed in the 18th Century. Made famous by Josiah Wedgwood.

CROCKERY or CROCKS Pots. Term for domestic ware. Not fine tableware but more every-day products. A little coarse, perhaps.

CROG ON Dialect. Cheat. Naughty.

CROOKED Pottery fault. Not straight. Faulty enough to be lump.

CROSS HATCH A particular pattern on an engraved copper plate used for pottery printing.

CROSS SEAMED When the separate parts of a plaster of Paris mould do not fit perfectly together then a fault will show in the cast piece. The cast from the mould will show as cross-seamed.

CROSSOMICAL Awkward and daft and irritating and moody person. Can be a pain in the neck. Sometimes very funny though.

CROWN Part of a bottle oven. The domed roof of the firing chamber.

CROWN DAMPER Equipment. Part of a bottle oven. A substantial hinged brick and iron flap operated by levers and pulleys from below to close or open the hole in the domed roof (or crown) of the oven.

CUP JOLLEY Equipment. Clay end. Machine for making cups. The jolley arm (or monkey arm) is brought down into the rotating cup mould to spread a ball of clay up the sides of the mould to form both the inside and outside shape of the entire cup.

CURTAIN Glaze fault. Sometimes cause by over glazing (too much glaze applied) so that large 'runs' are created in the glaze as it is fired and becomes molten.

CUT SPONGE DECORATION Process. Decorating department. Similar to Sponge Decoration where small sponges are dipped in coloured enamels, or glaze or slip and then dabbed onto the surface of the pot, but here only the hard stalk of the sponge plant is used. The stalk is loaded with ceramic colour and stamped onto the pot, often forming a border of repeated motifs or representing small flowers as part of a hand painted floral pattern (similar to potato printing).

Left: sponge decoration Right: cut sponge decoration

CUTHER Dialect. Gossip. Rude.

CUTTER Occupation. Printing shop. Usually female. The cutter uses scissors, or more usually a glass cutter's wheel, to cut printed patterns from a printed tissue paper pull from an engraved copper plate.

CUTTER Tool. Decorating department. Printing shop. Looks like a very small pizza slice wheel. Or glass cutter. Used to cut printed transfers into manageable shapes prior to transferring to the pot.

CUT UP Sad. Aww.

CUT UP A form of very expensive decoration where the applied gold has rich texture created by 'raising and cutting' into the underlying base of the gold. "Raised and Cut Up" may be peculiar to the Spode Factory, Stoke on Trent, England. more>